Bring a large pot of salted water to a boil and cook the whole wheat penne according to package directions until al dente.
While pasta cooks, season the chicken breast with sea salt and black pepper on both sides.
Heat olive oil in a large skillet over medium-high heat and sear the chicken until golden and cooked through, about 5-6 minutes per side.
Remove chicken from the skillet to rest, then slice into thin strips.
In the same skillet, add the broccoli florets and a splash of water, covering to steam for 3 minutes until vibrant green.
In a small bowl, whisk together the plain Greek yogurt, parmesan cheese, and minced garlic with two tablespoons of the hot pasta water.
Drain the pasta and return it to the pot, then toss with the creamy yogurt sauce, steamed broccoli, and sliced chicken.
Garnish with fresh parsley and serve immediately while warm.